Inaugural

google

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late 17th century: from French (from inaugurer ‘inaugurate’, from Latin inaugurare ) + -al.

wiktionary

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From French inaugural, from inaugurer, from Latin augurare(“to take omens”).

etymonline

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inaugural (adj.)

1680s, from French inaugural (17c.), from inaugurer "to inaugurate" (14c.), from Latin inaugurare "to inaugurate" (see inauguration). The noun meaning "an inaugural address" is recorded from 1832, American English.